The present invention relates to an inert gas generator having a burner, a flame or firing chamber, and a cooling arrangement for the generated inert gas.
In the transportation of combustible fluids or explosive gases on ships, large quantities of inert gas are necessary. The inert gas is, for example, admitted into tanks during or after discharge, for the purpose of preventing explosions. Furthermore, the storage tanks for storing natural gas or manufactured gas are constructed with double walls, and the resultant intermediate chamber is filled with inert gas. Under normal pressure, these gases held in the storage tanks may be transported in liquid form under appropriately low temperatures.
Since it has not been found economical to take along inert gas in storage tanks on board ships, fuel tankers have been equipped with inert gas generating equipment. In such equipment the liquid or gas combustibles such as diesel oil used also for ship propulsion are burned as completely as possible, so that the gas generated in this manner contains only thereafter carbon dioxide and nitrogen. The additional components as, for example, oxygen, carbon monoxide and sulphur dioxide, are either negligible in quantity or are removed by the washing processing following the combustion or burning. A general requirement for such an inert gas generating arrangement is that it must consume as little space as possible, so that the loading or cargo space of the ship is not unnecessarily reduced thereby.
Inert gas generating arrangements are known in the art in which a horizontally oriented cooling jacket surrounds a burning chamber which connects to a washing cooler. But such known arrangements are complex in design and are substantially large so that they occupy valuable space aboard ship.
Accordingly, it is an object of the present invention to overcome the disadvantages of known prior art arrangements and to provide an inert gas generator having a burner, a flame or firing chamber, and a cooling arrangement for inert gas, which is simple in design and requires substantially little space.
Another object of the present invention is to provide an inert gas generating arrangement of the foregoing character which may be economically fabricated and readily maintained.
The objects of the present invention are achieved by providing a rotationally symetric burner in substantially vertical relationship to a cylindrical flame or firing chamber. A cooling arrangement is provided, in accordance with the present invention, by a cooling jacket surrounding the flame or firing chamber. The cooling jacket is, furthermore, constructed in the form of a washing cooler. By constructing the inert gas generator in this manner a compact unit is obtained, and the burning as well as the cooling and washing of the generated inert gas is also realized. As a result, the inert gas requires only a drying process prior to being used.
A particularly advantageous embodiment of the present invention is obtained when the inert gas generator has a burner in which the cross section first widens and then narrows down again in longitudinal direction, so that the diameter of the flame or firing chamber is substantially 2.5 to 4.5 times larger than the largest diameter of the burner. The height of the flame or firing chamber is also to be substantially 1.5 to 3.5 times larger than its diameter. By taking into account the dimensions in the size of the inert gas generator, substantially good burning is obtained in the flame or firing chamber and sufficient cooling of the gases occurs prior to entrance in the washing cooler.
An advantageous construction of the inert gas generator in accordance with the present invention, furthermore, results when the washing cooler has an outer symmetrical housing with a cone or funnel-shape bottom and a cylindrical insert forming the flame or firing chamber. In the region below the lower edge of the insert, openings are provided for the passage of the gas and the washing order. In such construction of the present invention, the insert can be supported by the cone or funnel-shaped bottom.
The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.